The present invention relates to a gap filler that is installed at a platform in a railroad station to fill the gap between a train and the platform.
In recent years, gap fillers have been installed at platforms in an increasing number of stations. The platform gap filler is a device that protrudes a gap filler plate from the platform to reduce the gap between a train and the platform at the time of passengers' getting on and off. The platform gap filler stores the gap filler plate on the platform side at times other than during passengers' getting on and off, and protrudes the same to the railway track side at the time of passengers' getting on and off to narrow the gap between the platform and the train and prevent passengers' falling (for example, refer to JP-A-2005-14805).
A platform gap filler includes a brake mechanism and a lock mechanism that prevent displacement of a gap filler plate by reaction force of passengers' treading on the gap filler plate when the gap filler plate protrudes from the platform at the time of passengers' getting on and off.
The lock mechanism is operated by electromagnetic force as described in JP-A-2005-14805 and thus changing the locked state requires electric power. In addition, when power supply is shut off before the gap filler plate is fully protruded or fully stored, the brake in the electric drive mechanism is activated to make manual driving disabled. The train cannot be started with the gap filler plate in a position not fully protruded or stored. That is, the train cannot be started until the power supply recovers. To avoid such a situation, there is a need for a backup power supply enabling the release of the brake such that an instruction for releasing the brake can be issued in the event of a fault or power discontinuity.
Further, a platform may be located in not only a linear section but also a curve section of a railway track. To install the gap filler in the curve section of the platform, it is necessary to decide the amount of protrusion of the gap filler plate at each of installation positions because the gap between a train and the platform varies depending on the position of the door. Accordingly, it is necessary to design and manufacture the gap filler suited to the installation position. In this case, larger numbers of unique components and devices are used to cause a price increase. In addition, there may occur erroneous orders and wrong assembly at installation sites. JP-A-2005-14805 describes a method for avoiding this problem by which the brake is applied in the fully protruded position to fix the gap filler plate by braking force. In this case, however, if braking force is decreased due to the wear of the brake, the gap filler plate no longer can be fixed and the brake needs inspection.